I mean, launch costs are going down over time.
It might make much more sense to put many warheads up with a reusable system like falcon (~3000$/kg) than it does to maintain a fleet of necessarily single-use systems like minuiteman (7,000,000$/~300kg = 23,300$/kg). You might well be able to put four warheads with an equal mass of de-orbiting propellent into orbit (~1.7 km/s given solid propellent) for the same cost as one ICBM.
I mean, launch costs are going down over time. It might make much more sense to put many warheads up with a reusable system like falcon (~3000$/kg) than it does to maintain a fleet of necessarily single-use systems like minuiteman (7,000,000$/~300kg = 23,300$/kg). You might well be able to put four warheads with an equal mass of de-orbiting propellent into orbit (~1.7 km/s given solid propellent) for the same cost as one ICBM.